The constant-temperature device is widely used as a device to store specimens used for culturing and testing microbes or cells. The constant-temperature device has various instruments to keep environmental condition such as temperature, humidity and carbon dioxide concentration in a thermostatic chamber storing a large number of specimens to be cultured and tested. In case of culture, the thermostatic chamber is kept in a high humidity state equal to or more than 90% of humidity at temperature 37° C. In addition, culturing and testing continue for a long time, and therefore, in the process, it is necessary to change culture medium mixed with waste matter to new one if necessary by periodically examining and analyzing condition of each specimen.
Accordingly, many automatic constant-temperature devices with a memorization means, an operating means and a transport means have been devised up to date. These devices are provided with functions to automatically carry out taking in and out the container storing the specimen, to delivery to examining step and analyzing step, and to control the specimen condition, thereby enabling to efficiently carrying out culture and test for a long period.
When atmospheric unwanted bacteria, previous cultured cells or microbes remain in the thermostatic chamber, the constant-temperature device adversely affects the objective cells and microorganisms in new culturing and testing. Therefore, an operation called sterilization is required for the inside of the thermostatic chamber to remove bacteria before starting culturing or testing. The conventional constant-temperature device with an automatic conveyance mechanism has adopted a sterilization method for irradiating ultraviolet rays or a sterilization method for wiping off with medicinal solution. However, there recently appear constant-temperature devices with an automatic conveyance mechanism that have no motors and no electronic members in the thermostatic chamber, thereby enabling use of a sterilization method called dry sterilization for killing the unwanted bacteria by keeping inside temperature equal to or more than 130° C.